Whether you're Irish, or Irish at heart, I hope you have a magnificent St. Patrick's Day! In between your bouts of green beer and Irish food today, you might be interested in a little factoid I dug up on the Internet.
You may have heard the legend of Saint Patrick, who is said to have driven all the snakes out of Ireland. While good ol' Saint Pat might have done some amazing things in other respects, the absence of snakes in Ireland was not actually his doing. Wikipedia also mentions that New Zealand, Iceland, Greenland and Antarctica are also snake-free (make a note of that, ophidiophobics).
There's a very interesting article at Popular Science about Ireland's snakeless state. While Ireland is currently free of native snakes, there are pet and zoo snakes living there. Imported snakes are not illegal. However, if these pets get free of their owners, they run the risk of becoming an invasive species. As anyone in Australia can tell you, invasive species are bad news. Snakes have many uses, but in a foreign environment with no limiting factors, they could be devastating to an ecosystem.
For now, though, Ireland remains largely snake-free, so you can sip that green beer and listen to some traditional Irish harp music. Sláinte!